The tsunami of April 1, 1946 broke over Pier No. 1 in Hilo Harbor, Hawaii. The man in the foreground (lower left) became one of the 159 deaths on the islands.
Credit: NOAA
A mystery surrounding one of the most destructive tsunamis of the 20th Century just got more puzzling as a seafloor search failed to reveal the smoking gun scientists expected to find.
On April Fools Day in 1946 an earthquake off the coast of the Aleutian Islands in Alaska spawned a series of waves known as a tsunami. One wave as high as a 13-story building hit locally. Others raced across the Pacific, killing dozens and leaving a trail of destruction that stretched to California and even South America.
The earthquake was too small to spawn the huge local wave, many scientists agree, and they have struggled for decades to figure out what happened. The leading theory has been that the earthquake triggered an underwater landslide, generating a one-two punch.
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But a seafloor-mapping project by Scripps Institution of Oceanography, designed specifically to look for the cause of the tsunami, didn't find evidence to support that theory.
"We found no landslide where there should have been a landslide, where I was positive there had to be a landslide," Gerard Fryer, a geophysics professor at the University of Hawaii, told LiveScience. "I was stunned that there was nothing there."
Complex waves
How tsunamis grow larger at the shore.
Credit: LiveScience/Robert Roy Britt Tsunamis can result from earthquakes in the seafloor, underwater landslides, and more rarely volcanic eruptions. Even an asteroid impact can trigger one.
Whatever the cause, two tsunamis are created. A local one moves toward the nearest coastline, and another travels into the deep ocean. In each case, the tsunami is actually a series of waves, much like what you can produce by paddling your hand in the bathtub.
The word tsunami is Japanese for "great harbor waves." On the open ocean, however, they are barely noticeable, looking from the surface like any other wave. But underneath, a tremendous well of energy lurks.
The height of a tsunami is not apparent until it travels up from the deep sea into the shallow waters along a coastline and rushes inland. Just as the your bathtub waves splash up the edge, tsunamis are forced upward to varying extent depending, in part, on the slope of the shore they meet.
Contrary to popular belief the surge of a tsunami does not appear as a great crashing wave. Rather, it is a very strong and fast moving tide that can destroy homes, overturn train cars, and deposit boats several block inland. Hawaii takes the brunt
The first wave of the tsunami on that April 1st nearly six decades ago reached the big island of Hawaii in about five hours. The Hilo waterfront was destroyed. Surges as tall as two- and three-story buildings pounded several coastal villages. In Haena, the tsunami reached its maximum height — in Hawaii, anyway — of 45 feet (13.7 meters).
In 1946
Mr. [Hilario] Aquino said that when the waves hit the church, he was tossed out amidst the children. He swam about rescuing the children and lifting them up into the large trees of the church yard. When the waves subsided, 10 of the children were safely clinging to the trees and their parents all agreed that Mr. Aquino had saved their lives. -- From the Honolulu Star Bulletin, April 05, 1946
The calamity killed 159 people in Hawaii and caused $26 million in damage — in 1946 dollars.
The Pacific Ocean is a big place, and the waves spread. Surges up to 14 feet swamped Half Moon Bay, California. One person drowned in Santa Cruz. Fishing boats were damaged as far south as Chile.
The local tsunami in Alaska rose as high as 138 feet (42 meters), according to research by Emile Okal at Northwestern University. It destroyed the steel-reinforced Scotch Cape lighthouse on Unimak Island.
It was this local surge that Fryer and Okal agree could not have been spawned by the earthquake alone. Doesn't add up
The 1946 Alaska earthquake had a magnitude of 7.1. Based on what scientists understand about the energy and characteristics of the earthquake, it should not have been able to generate either such a large local surge or such a devastating Pacific-wide tsunami. The idea of a landslide contributing to the total energy was paired by some scientists with a theory that the earthquake was larger than the instrumentation of the day could measure.
Okal studied the earthquake and its aftershocks, which originated across a broader area than would be expected. That suggests the main temblor was more of a slow rumble than an abrupt break in the planet's crust.
The slow movement, Okal says, would have been difficult for seismometers of the era to measure. He calculates a true size of the earthquake at around magnitude 8.5, which comes close to accounting for the tsunami's effects in Hawaii.
Yet questions surrounding the size of the local tsunami, the taller one that came ashore in Alaska, remain following the Scripps Institution's seafloor mapping expedition, which was conducted in July.
"We found seafloor evidence that will cause tsunami modelers to rethink the cause and characteristics of the 1946 tsunami," Tony Rathburn, a faculty member at Indiana State University, said in a statement last month. "Our findings make the causes of the 1946 tsunami even more mysterious." Not giving up
Okal says it still may be possible a landslide was involved in the complex events of 1946. He said there are important variables, including where the Scripps project looked and the size of landslide the searched for.
"If they were looking for an elephant and there was only a dog, they could say there was no elephant but they weren't even looking for the dog," Okal said in a telephone interview last week.
Fryer has some new ideas that might resolve the mystery, but he's not ready to share them. He and Okal both plan to stick with the investigation.
"Almost 60 years after the event, the 1946 tsunami is still making fools of all of us," Fryer said.
Big Island Lava Flows Reach Site Of Geothermal Plant
A naturally occurring berm has so far halted the flow’s advance, but officials warn if the lava does hit the plant’s underground wells it could trigger the release of poisonous gases.
Lava erupting from the Kilauea volcano has reached the property of a geothermal power plant where toxic gas lurks in underground wells, the head of the state emergency management agency said Monday.
So far, a berm has halted the advance of the lava at about 200 to 300 meters from the wells of Puna Geothermal Venture.
But if the lava interacts with the wells of the Puna Geothermal Venture, it could trigger an uncontrolled release of deadly hydrogen sulfide, Thomas Travis, administrator of the Hawaii Emergency Management Agency said during a press conference Monday.
When the Puna Geothermal Venture is operating normally, the wells feed steam into a turbine that produces 25 percent of the Big Island’s electricity.
The Puna Geothemal Ventures plant on the Big Island.
Ormat Technologies Inc.
“If you put tremendous heat on any metal, it changes how much pressure and stress that metal can hold,” said Travis. “That’s why having lava flow across the well causes some uncertainties that have to be dealt with.”
The wells were shut down weeks ago when the eruption started.
Over the past two weeks, 10 wells have been quenched, and capped with a heavy steel plate. The work required removing the massive wellhead valves tested to resist 3,000 pounds per square inch of pressure, something that will now be accomplished by a column of water more than a mile high to resist lava entry into the well underground.
That’s the working theory anyway, and company and government emergency management officials consulted experts worldwide from New Zealand to California to Iceland on the best response to imminent lava inundation.
The trouble is, “to our knowledge, no one’s faced this before,” Travis said.
The last wellhead – Well 14 – stymied all efforts Monday to quench and cap the well. More than a mile of cold water was not enough. Ditto more than a mile of denser salt water.
“Something has happened down there in the last two weeks that won’t let it (quench),” Travis said.
Drilling mud, a highly complex and heavyweight chemical compound used extensively in oilfield drilling, is the next line of attack. Travis was confident the mud would work because it hardens and thickens under heat and pressure, he said.
That work is supposed to be complete by Tuesday, Travis said.
Wells already quenched are then sealed with a heavy steel plate at the bottom of a 30-foot hole, then backfilled with insulating cinder, said Talmadge Magno, Hawaii County’s Director of Civil Defense and a member of the four-person oversight committee appointed by Hawaii County Mayor Harry Kim and Hawaii Gov. David Ige to handle the PGV emergency.
The lava, which crossed onto the southern edge of the PGV property early Monday, is 100 to 200 meters from the plant’s 11 wells, Travis said at a Monday afternoon news conference.
Although a naturally occurring berm has so far halted the lava’s advance, officials are preparing for the worst.
The natural swale in the land is holding so far. But when it fails, only then will everyone know if the emergency response has worked.
In daily power-generation operations, deep underground fluids under pressure and heated to 350 degrees centigrade, are tapped by PGV’s production wells. The super-heated fluids rise to the surface to exchange heat with pentane, whose boiling point is lower than that of liquid propane, the gaseous pentane then powers the turbines to spin electricity from a magnetic field.
Contacted last Friday before the nearby rifts erupted into high volume lava emissions, PGV’s Mike Kaleikini was already worried about the destructive possiblities of the East Rift eruption of 2018.
The plant is owned by Ormat Technologies and sells power to the Hawaiian Electric Light Co., the Big Island’s electric utility that is part of the Hawaiian Electric Cos.
The plant made some $11 million in profit in 2017 for Ormat and and a smaller consortium of investors, CEO Isaac Angel said earlier this month in a conference call with investors.
Employing about 30 full-time staff, Puna Geothermal is a major force in the island’s power generation grid.
If the Puna Geothermal plant is damaged or destroyed, PGV has a $100 million insurance policy, Angel told investors in the conference call.
“It’s not easy to predict where it’s going to go and when it’s going to get there,” Travis said, “so it’s important we get what we can get done now.”
Civil Beat correspondent Andrew Perala contributed to this story from the Big Island.
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The governor has requested assistance for the flooding on Oahu/Kauai. Public Assistance was approved and Individual Assistance was not approved, but we believe the governor will appeal that determination.
On the Big Island, county and state agencies are explaining what is available, but there is no FEMA assistance for individuals and businesses authorized at this time. While it is not safe for people to remain in the primary affected areas in Lower Puna and related areas, most of the Big Island remains very safe for residents and visitors. We don’t want to underestimate risks but also recognize the impacts of those off the Big Island presuming that it is not safe to live or visit.
Since our role is to support, we will continue to fill that role. Please remember that FEMA is not in charge of disaster management, we lend support to local, state, tribal and community-led efforts.
We have staff working side-by-side at the Hawaii County and state emergency operations centers, and the rest of the FEMA team is eager to deliver help within the authorities currently available.
David
From: Ruthie Caudill [mailto:ruthiejim13@gmail.com] Sent: Monday, May 21, 2018 10:32 AM
We also know that thousands of N95 masks have been distributed to the public, but we emphasize that the masks guard against ash and other particulates but not gases.
And now:
On the masks, I have seen and heard consistently solid warnings about gases and particulates, the limits of the masks and the most critical message which is to stay away from hazardous areas.
There are no safe areas as far as I am concerned. The gases and particles are so small that many people are unaware.
Could FEMA come out with some sort of statement about the Governor not applying for Emergency Assistance for the Kauai/Oahu Flood?
There are many who have lost their homes, have nothing to eat, and living on the beach in tents, or other places, and are unaware that they could have had help if the Governor had applied for Emergency FEMA.
Could FEMA also make a statement as to the help that is available for the people on the Big Island, who are trapped?
Thanks for your latest messages. First, there are no “FEMA masks.” I feel strongly that I need to reiterate the role of FEMA as a support agency to state and local authorities in response to the Kilauea incident and the flood recovery that is beginning on Kauai and Oahu.
On the masks, I have seen and heard consistently solid warnings about gases and particulates, the limits of the masks and the most critical message which is to stay away from hazardous areas.
FEMA will reimburse local and state agencies for the expenses they incur managing evacuation and sheltering. Additionally, FEMA will reimburse federal agencies, such as the Department of Defense, if federal military assets are needed to support evacuations, but at this point, that has not been necessary. As to the amounts of money reimbursed, we are too early in the process for the local and state agencies to have submitted requests.
The same is true for the public infrastructure rebuilding that FEMA will pay for related to the April flooding. The state organizes kickoff meetings for organizations interested in applying for federal funds, and those meetings will take place this week in Oahu and Kauai.
I hope this message addresses your latest questions.
From: Ruthie Caudill [mailto:ruthiejim13@gmail.com] Sent: Monday, May 21, 2018 9:29 AM
If I see evidence of fraud, waste or abuse related to FEMA’s disaster programs, I will contact the Office of the Inspector General. However, since the concerns you raised were related to looting and poaching, I don’t believe those relate to the DHS OIG’s authorities. However, any concerned individual may report fraud, waste or abuse. Details are found here: https://www.oig.dhs.gov/about/contact.
Thanks for your messages over the weekend. I am sorry to hear reports of looting and poaching. Research shows that in most disasters, criminal activity declines, but unfortunately, we know that the decline is not universal. For your awareness, FEMA has no law enforcement authorities, so the issues being reported are within the jurisdiction of other agencies, and principally, local and state authorities.
In large scale emergencies, states can request public safety support, and federal assets may be used to augment local and state resources, but again, FEMA has no law enforcement authorities or assets. If we or the public believes federal disaster resources are being misused or abused, the Department of Homeland Security’s Office of Inspector General has a role in investigating and working with prosecuting authorities.
You also sent a message with a photograph of what appear to be members of the Hawaii National Guard and a school bus. FEMA is supporting and amplifying the public safety messages related to lava, ash and toxic gases. The most important action any member of the public can take is to stay away from hazardous areas. Based on ongoing air monitoring at all levels of government, the Hawaii County government has allowed some residents to return to their properties to retrieve additional belongings, check on pets and properties, etc. We also know that thousands of N95 masks have been distributed to the public, but we emphasize that the masks guard against ash and other particulates but not gases. The level of exposure of soldiers staying outside for longer period of times than a bus driver or students driving through an area with the bus windows closes, may explain the difference in level of protection.
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